Another report has criticised the work of Professor Jonathon West's group which was charged with verifying the conservation value of Tasmania's forests.

The Institute of Foresters of Australia say the Independent Verification Group's processes are highly flawed because of time constraints and narrow terms of reference.

The institute says the reports fail to consider the contribution of current reserves and forest management practices.

It also says the reports have failed to fully assess the impacts of reserves on stakeholders such as tourism operators and beekeepers and has put great pressure on private landowners who have native forests for logging.

It adds that Prof. West did not ask the institute to review his reports as promised.

The institute has written to the Prime Minister, Julia Gillard, complaining that it was not properly consulted.

State-owned Forestry Tasmania has also criticised the group's 2,000 pages of review of the forest industry, suggesting it could be biased.